WASHINGTON – J.D. Williams didn't think much about the smoke cloud that often shrouded his air base in Iraq. Not when it covered everything he owned with black soot or when his wheezing and coughing made it difficult to sleep at night.

“We just went about our business because there was a war going on,” said Williams, a retired chief warrant officer who was responsible for maintaining some 250 aircraft for the U.S. Army's 101st Airborne Division.

He returned home from that second stint in Iraq in 2006 and subsequently was diagnosed with an irreversible lung disease that his doctor suspects could be related to smoke from one of the hundreds of burn pits that dotted Iraq and Afghanistan during the course of the two wars. The pits were used to burn off the garbage that accumulates at military bases, everything from Styrofoam and metal to paints, solvents, human waste and medical waste.

A new Department of Veterans Affairs registry, mandated by Congress, will be used to try to determine whether there is a link between the burn pits and long-term health problems.

Military personnel who were stationed near an open burn pit can sign up. Researchers will use the database to monitor health trends in participants, and the VA will alert them to major problems detected.

Over the long term, the findings could make it easier for veterans who served near burn pits to obtain disability payments.

Williams, 56, of Huntsville, Ala., was initially told that he would have to prove that his illness, diagnosed as constrictive bronchiolitis, was service-related. He walked out of the room. Eventually, after he traveled to Washington and met with members of Congress, the VA increased his disability rating 10 percent.

If researchers find certain illnesses are linked to exposure to burn pits, then the VA would be more likely to declare those illnesses a presumptive condition, eliminating the need for a veteran to prove that his or her illness is service-related.

Sixty-three burn pits were still being used in Afghanistan as of Dec. 26; those in Iraq were closed by December 2010. Camps with fewer than 100 people are not required to report the use of a burn pit, so there could be more, but generally much smaller ones.